The improvement and success of socio-technical systems depend on the joint optimisation of both the social and the technical parts. Improving the social part of a socio-technical system is a meticulous task, as social requirements are diverse and dynamic, and they usually evolve with time and context. Information transparency (henceforth, transparency) is one of the social requirements that can affect the overall attitude of the stakeholders present within a socio-technical system, and influence their other social requirements such as privacy, trust, collaboration and non-bias. In this paper, we advocate the need to engineer transparency as a first class requirement, propose a baseline model for transparency and show how this model can be a starting point for the analysis of transparency requirements of different stakeholders. We showcase our on-going research in the modelling and analysis of transparency as a requirement, discuss some of the challenges of transparency requirements elicitation, and present our future work.